Illite-smectite rich clay parageneses from Quaternary tunnel valley sediments of the Dutch Southern North Sea – mineral origin and paleoenvironment implications

The Pleistocene sediment infill of elongated glacial incisions of the Southern North Sea (SNS) often is referred to as tunnel valleys (TV). Its depositional environment is not yet fully understood and present study addresses this challenge from a perspective of clay mineral transformation (illite to I-S) reported from the largest Elsterian TV of SNS. Material acquired from the K14-12 borehole in the Dutch offshore was analyzed by X-ray diffraction, electron microscopy, electron microprobe analyses, and laser particle-size analysis. Illite and illite-smectite appeared as dominant clays along wi... Mehr ...